Cylinder lock



Dec. 8, 1925- 1,564,883

J. A. MUZZIO CYLINDER LOCK.-

Filed May 25 1923 Patented Dec. 8, 1925.

UNITED STATES PATENT OFFICE.

JAMES A. MUZZIO, OF CLEVELAND, OHIO.

CYLINDER LOCK.

Application filed May 25, 1923. Serial No. 641,393.

I and is an improvement upon the invention described and claimed in my prior application forcylinder lock, filed January 13, 1922, Serial No. 528,952.

The present invention has more particular relation to the cylinder, plug and tumbler mechanism, regardless of how these parts are supported or what devices the lock operates or controls. The objects of the invention are to improve the construction and arrangement of the tumbler controllingv springs and the channels in which they work to thereby enable the parts to be-more compactly arranged in a shorter and smaller plug and with more positive tumbler operation; to rovide improved means for preventing etachment or separation of the cylinder and plug except by authorized persons; to provide a releasable connection between the cylinder and plug actuated by magnetic means and therefore likely to escape discovery by unauthorized persons, to provide improved means for safeguarding the lock against opening by sawing and specifically by embedding within the softer material thereof hardened steel wire or other saw resisting material; and finally to simplify the plug construction and reduce the number of forming operations by opening the plug end with a recess forming a centering opening useful in lathe work on the plug and which later may be used for a key iding opening.

Furt er objects of the invention are in part obvious and in part will appear more in detail hereinafter.

In the drawings, Fig. 1 is a front view of the cylinder and plug of a lock embodying the invention; Fig. 2 is 'a sectional elefation on the line 22, Fig. 1 showing the lock ap lied to a receptacle and the parts operate by the rotatable plug; Fig. 3 is a sectional elevation on the line 33, Fig. 2; Fig 4 is a sectional view on the line 44,' ig. 1 and showing the key in'place; Fig. 5 is a similar view with the key removed; Figs. 6 and 7 are views corresponding to Fig. 4 and illustrating respectively the cylinder and plug; Fig. 8 is a cross section on the line 88, Fig. 5, the key being omitted and the tumblers being shown in looking position; Fig. 9 is a similar view with the key in place and the plug partly turned in the cylinder; Fig. 10 is a cross section on the line 10-10, Fig. 4 with the key in place and the plug partly turned; Fig. 11 is a cross section on the line 1111, Fig. 2, but showing a modified form of means for preventing separation of the cylinder and plug; and Fig. 12 is a detail view of a key with a coil thereon.

The locking mechanism shown in the drawings comprises a suitable cylinder or barrel 1 in which is rotatably mounted a key receiving plug 2, rotation of which is permitted or prevented by the effect of the key 3 upon a series of pivoted tumblers or levers 4 cooperating with longitudinally extending grooves or channels 5 in the cylinder. Rotation of the plug may control or operate any suitable locking devices. For purposes of illustration said plug is shown as provided on its rear end with a cam portion 6 flattened off on two sides, as at 7 so that plug'rotation operates two looking levers 8 pivoted at 9 in the lock casing 10 and having recessed strike receiving ends 11 yieldingly pressed towards each other by the spring 12, the recesses therein being adapted to receive projections 13 'on a strike member 14 carried by one member 15- of the two parts to be locked together, the other member 16 having an opening in which the barrel 1 is secured by attachment thereto of plates 17. The longitudinal recesses 5 before referred to are distributed circumferentially around the inner surface ofthe cylinder and may be of any suitable number, four bein shown. To cooperate with said recesses t e plug carries four sets of tumblers, two in each set, the two tumblers of each set being shown in tandem and lying in diametrically extending throughslots 19. of the plug. Each tumbler hasa tail portion 20 adapted to engage a rib or flange of the key shank and to be properly located in either looking or release position by the configuration of the ke r1b, and also has a small ivot pin 21 ying in a short circumferentially extending recess 22 of the plug. To move said tumblers to lock-' ing positlon each tumbler has bearing levers longitudinally in tandem, and also to group the forward four and the rearward four opposite or in circumferential alignment with each other and enables the entire plug to be shortened more than where a staggered arrangement of levers is used.

The springs 22, as shown, lie in annular grooves 24 in the plu the bottoms of said ooves being tapere or inclined as at 25,

ig. 7. This arrangement enables each spring arm to move nearer to the central axis and thereby produce a more positive or powerful turning effect upon its tumbler and move it to an extreme extended or locked position, as shown in Fig. 5, but without unduly weakening the plug.

The diametrical slots 19 in which the tumblers work are made-b slotting the plu through from side to si e. Preferably sai slots do not extend clear to the end of the plug, which is left unslotted and circumferentially intact to increase the strength of the parts. T0 avoid the necessity of extending these slots endwise out through the end of the plug to formthe key receivin opening I preferably start the formation 0 the plug with a drilling operation, forming an end recess 26 with a conical bottom 27. This depression is used as a centering opening in turning up the plug in the lathe to cylindrical form and as it extends into the body ofthe plug the simple formation of the diametrically extending slots 19 in the plug body leaves the ends of such slots open into the recess 26 so that in the finished lock said recess becomes a key-guiding opening.

Suitable means may 'be provided for preventing unauthorized separation of the plug and barrel. For example, Fig. 2 shows the plug provided with a rigid radially extending pin 28 turning in an annular groove 29 in the wall of the barrel. Said pin may be introduced into the annular groove by a longitudinally extendin gate or recess 30 so that the plug and arrel can only be separated in one position, after the manner of a bayonet slot joint, but if desired, .said

gate may be omitted and the construction shown in Fig. 11 employed. In this arrangement the pin 28 is backed up by a light compression spring 31. The pin is pushed down into its opening and the plug moved into the barrel until the pin sna s into the annular recess 29. Ordinarily the parts would thereafter be permanently connected, but in this case the plug or barrel is usually made of bronze, brass or some non-magnetic metal and the key of steel or iron. Therefore, by making the shank of a proper key the core of an'electro-magnet, such as by winding a wire coil 32 (Fig. 12) around a portion of the shank of the key and passing electric current through said coil, the key can be introduced into the lock withdrawn it from the recess 29, enablin the plug to be withdrawn from the barre Preferably also the lock is provided with suitable means for perventing tamperin by sawing. As shown the inner surface 0 the barrel is provided with one or more, two bein shown, of annular grooves 32 in each 0 which is a split ring of hardened or spring steel wire' 33. Such wires will interfere with sawing operations and avoid the possibility of opening the look by such means.

What I claim is: g 1. A cylinder lock, comprising relatively rotatable cylinder and plug members, said plug having a diametrically extending slot 1n a plane'pa'rallel with its axis. said slot terminating short of the plug end, and'said plug having a key receiving and centering opening at one end intersecting said slot.

2. A cylinder lock, comprising relatively rotatable cylinder and plug-members, means for securing said parts to each other in a manner to permit relative rotation but prevent relative longitudinal motion therebetween, and electro-magnetic means for releasing said members for relative longitudinal motion. v

3. A cylinder lock, comprising relatively rotatable cylinder and plug members, circumferentially spaced longitudinally extending locking levers lying and movable in radial slots of the plug, and a series of springs lying in the plug, one between each circumferentially spaced pair of levers, each spring having two oppositely extending arms each engaging a lever. said springs each extending less than 180 around the plug axis.

4. A cylinder lock, comprising relatively rotatable cylinder and plug members, circumferentially spaced longitudinally extending locking levers lying and movable in radial slots of the plug, a series of springs lying in the plug. one between each circumferentially spaced pair of levers, each spring having two oppositely extending arms each engaging a lever, said springs each extending less than 180 around the plug axis, the plug being provided with annularly extending grooves to receive said springs, and the bottoms of said grooves being tapered.

5. ,A cylinder lock, comprising relatively rotatable cylinder and plug members, keycontrolled lockinglevers in the plug coopand will magnetically attract the .pin and 1 crating with recesses in the c linder, one of said members being provide with annular rotatable cylinder and plug members, keycontrolled locking levers in the plug cooperating I with recesses in the cylinder, the

cylinder having a series of internal annularly extending grooves, and rings ofsaw" 10 resisting materlal lying in said grooves.

In testimon signature.

y whereof I hereby aflix my JAMES" A. MUZZIO. 

